Time Division Duplex (TDD) systems allow one or more Access Points (APEs) to bidirectionally communicate with Customer Premises Equipment (CPE) such as mobile telephones. As many APEs (also known as hubs) and a multitude of CPEs may be operational in a system, it is important that strict timing protocols be observed to avoid communication conflicts. In multi-sectored systems, time slots allotted to each sector also include guard times to prevent the activity of one sector from encroaching upon the designated time slots of other sectors.
Typical prior art TDD systems incorporate highly stable voltage controlled oscillators (VCOs) in the hubs to provide accurate timing control. In addition to being expensive, such approaches also require transient periods of up to twenty-four hours before the local oscillator has achieved suitable stabilization.
There is a great need to provide in a TDD system, a Time Division Multiple Access architecture that incorporates timing generators that are both low cost, and that achieve stabilization shortly after they are activated.